
Sirius Black Feminised
Grow Sirius Black Feminised in the UK. Indica genetics at 24% THC, known for euphoric, creative effects.
Royal King Genetics — first-party test batch
Figures below are from our internal seed-lot QC and verified UK grower submissions, not breeder marketing. Determined from a single batch tested 2026-09-07 on 375 seeds.
About Sirius Black Feminised
Where you grow Sirius Black in Britain matters less than when you start it. This is one temperate maritime climate with a real north-south gradient: the south coast opens and closes its season around a fortnight either side of the central belt or upland Wales. Heat is almost never the constraint here. The wet finish is — rain sitting in dense flower through late September and October is what starts botrytis, and it ends more British outdoor crops than every insect on the plot combined. That puts the 9-10 weeks flowering window and the bud structure ahead of everything else on this page. Under lights none of it applies: daylength, temperature and humidity are yours to set, and Sirius Black can be run anywhere in the country on its merits.
The pressures on a British grow are fairly predictable. Damp is the first of them: botrytis in dense flower from September on, answered with open bud structure and moving air rather than with a spray. Indoors it is spider mite and thrips that arrive, and humidity above 60% in late bloom is what turns a contained problem into a lost room. Outdoors in a wet spring the slugs take more seedlings than every insect put together, and they do it overnight.
Flavour, aroma and effect
Sirius Black arrives in stages. The first draw at 24% THC brings dry pepper that registers at the back of the throat. The euphoric, creative character follows within minutes, starting as weight behind the eyes and working down through the shoulders and chest. By about a quarter of an hour it has become a physical stillness — not sedation so much as a strong disinclination to get up. Two to three hours at a moderate dose. The myrcene underneath adds body and depth beneath the rest.
Terpene breakdown
Primary: Caryophyllene · Secondary: Myrcene · Tertiary: Bisabolol. This combination turns up often in cultivars that win things, and it is usually the one growers comment on when a jar is opened for the first time after curing. Caryophyllene anchors the aroma, myrcene occupies the middle, and bisabolol sits behind both — which is the part that separates this strain from others sharing its primary terpene.
Who it suits
Who does well with Sirius Black? Indoor growers who want the timeline under their own control. Outdoor growers who want to choose when flowering starts. Anyone with the room and the patience to veg it properly before flipping. Difficulty is rated intermediate, which means a moderate learning curve that rewards attention without demanding a laboratory.
Effects
Strain Type
Strain Data Sheet
Packaging
Feminised Premium
Seeds
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Sirius Black Feminised — Breeder Information
Royal King GeneticsBred and stabilised in-house by Royal King Genetics — our internal breeding team. Every batch is QC'd and germ-tested above 99% before it ships. Read the full breeding process and about page.
Sirius Black runs through our F4 programme. Four cycles of phenotype selection have removed the worst of the trait variation; what is left is a tight, predictable population for production.
Cull off-type phenos in Sirius Black through filial selection.
Chosen for resin output, a low-slung stature and a clean indica terpene fingerprint.
Royal King Genetics select-mother programme — pollen drawn from an internally maintained reversed-female line.